The present invention relates to TEM (transverse electromagnetic) cells, such as are used for performing radiated electromagnetic (EM) susceptibility testing or for measuring radiated EM emissions from electronic or electromechanical equipment.
The standard TEM cell is a rectangular, coaxial line that serves as a broadband, linear phase and amplitude transducer, in the sense that it converts field strength to RF (radio-frequency) voltage or RF voltage to field strength. Such cells are commonly used either to establish standard electromagnetic (EM) fields for susceptibility testing of electronic equipment, or to detect radiated emanations from electronic equipment. Briefly, the cell includes an outer metal shielded enclosure for enclosing the equipment to be tested, which shielded enclosure is formed with tapered end sections at its opposite ends defined by a plurality of inclined walls; an inner metal septum plate extending along the longitudinal axis of the shielded enclosure; and a connector assembly connected to each of the two tapered ends of the shielded enclosure for connection to the cell generator and cell load, respectively. Further details of the construction and operation of such TEM cells are available in published literature, for example, in NBS Technical Note 1013, published by the National Bureau of Standards, titled "Using a TEM Cell for EMC Measurements of Electronic Equipment."